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Aminoglycoside-induced hearing loss in a patient with the 961 mutation in mitochondrial DNA

Mizuki Yoshida1, Tomoro Shintani, Motoyasu Hirao

  • 1Department of Otolaryngology, Sapporo Medical University, Sapporo, Japan. yoshidam@sapmed.ac.jp

ORL; Journal for Oto-Rhino-Laryngology and Its Related Specialties
|May 31, 2002
PubMed

Insights

A mitochondrial gene mutation, delT961Cn, predisposes individuals to aminoglycoside-induced deafness. Genetic screening for this and other mutations can help prevent irreversible hearing loss.

Area of Science:

  • Genetics
  • Otolaryngology
  • Molecular Biology

Background:

  • Aminoglycoside antibiotics can cause hearing loss.
  • The A1555G mutation in mitochondrial 12S ribosomal RNA is a known risk factor for aminoglycoside-induced deafness.
  • A recently identified mutation, delT961Cn, also in the mitochondrial 12S ribosomal RNA gene, has been linked to aminoglycoside sensitivity.

Observation:

  • This study reports on a Japanese patient with streptomycin-induced deafness who carried the delT961Cn mutation.
  • The patient's case provides clinical evidence for the role of delT961Cn in aminoglycoside-induced hearing loss.

Findings:

  • The delT961Cn mutation plays a significant secondary role in the development of aminoglycoside-induced deafness.
  • This finding expands our understanding of the genetic factors contributing to ototoxicity from aminoglycosides.

Implications:

  • Family history and molecular screening for mutations at positions 1555 and 961 can help identify at-risk individuals.
  • Proactive genetic screening may reduce the incidence of irreversible hearing loss caused by aminoglycoside treatment.
  • This approach could prevent tragic hearing loss in susceptible patients.

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